procedure PopUntermenue(OWNR, X, Y, MH, UM: Integer); 
begin 
  TrackPopupMenu(Getsubmenu(MH, UM), TPM_LEFTBUTTON or 
    TPM_LEFTALIGN, X, Y, 0, OWNR, nil); 
end; 
 
 
// Beispielaufruf 
 
procedure TForm1.FormMouseUp(Sender: TObject; Button: TMouseButton; 
  Shift: TShiftState; X, Y: Integer); 
var 
  p: TPoint; 
  welches: integer; 
begin 
  if Button = mbRight then begin 
    welches := 0; 
    GetCursorPos(p); 
    PopUntermenue(handle, p.X, p.Y, MainMenu1.Handle, welches); 
  end; 
end;